Galaxy number counts at second order: an independent approach

Next generation surveys will be capable of determining cosmological parameters beyond percent level. To match this precision, theoretical descriptions should look the linear perturbations to approximate observables in large scale structure. A quantity interest is Number density galaxies detected by our instruments. This has been focus recently, and several efforts have made explain relativistic effects theoretically, thereby testing full theory. However, results at nonlinear level from previous works are disagreement. We present a new independent approach computing galaxy number counts second order perturbation derive analytical expressions for observed redshift, angular diameter distance volume spanned survey. Finally, we compare with which compute general distance-redshift relation, finding that result agreement order.